1. Field
The present disclosure relates to an oxide electronic device and a method for manufacturing the same. More particularly, the present disclosure relates to an oxide electronic device, which allows electric conductivity of two-dimensional electron gas (2DEG) generated at an interface of heterogeneous oxides to be controlled stably in a non-volatile mode, as well as to a method for manufacturing the same.
2. Description of the Related Art
Electronic devices, such as transistors, which repeat logging and deletion of data, have high convenience. Due to this, electronic devices, such as transistors, are used widely in portable memory media, including a USB memory and memory card, or a radio-frequency (RF) tag as a medium for radio-frequency identification (RFID) performing wireless reading of information.
In general, silicon (Si) materials are used in most electronic devices. However, it is expected that silicon materials reach the limit in downsizing and functional upgrading within the next 10 years. Therefore, in order to overcome the limit of conventional Si materials, active studies have been conducted to develop novel materials substituting for Si. As typical examples, there are nitride materials, such as GaN-based materials, and oxide materials based on a metal-oxide structure.
In addition, many attempts have been made to realize electronic devices, such as transistors, by using two-dimensional electron gas (2DEG). This is because 2DEG has not only high charge mobility but also specific quantum dynamic characteristics unique to 2DEG. Due to such characteristics, it is possible to overcome the limit of a silicon (Si) material in downsizing and functional upgrading. Particularly, 2DEG is generated at the fusion interface of heterogeneous materials different from each other. For example, Korean Patent Publication Nos. 10-0413523, 10-0770132 and 10-0857683 disclose nitride devices based on a nitride material and using 2DEG generated at an interface between a GaN layer and AlGaN layer.
Recently, oxide materials have been spotlighted more. Oxide materials have higher conductivity as compared to Si materials or nitride materials, show various properties, including dielectric properties and magnetic properties, and facilitate fusion of heterogeneous materials due to a similar crystal structure. Therefore, it is possible to realize multifunctional devices having novel characteristics when using oxide materials. Herein, controlling electric conductivity of 2DEG by using external electric stimulation is a highly important technology in realizing oxide-based electronic devices, and also affects the characteristics of electronic devices.
According to the related art, charge injection through a metal gate electrode or conductive probe tip has been used to control electric conductivity of 2DEG of oxide devices. However, in this case, the electric conductivity of 2DEG controlled by such charge injection tends to have volatility with time, and thus is not maintained stably but experiences a change. In this context, there is a problem in that continuous application of electric energy is required to prevent such volatility. As a result, the resultant device requires a large amount of driving energy.